All of our gates are hung from pressure treated wood posts. I had a welder come & attach a 5" diameter sliding pipe with a handle which securely inserts into a large hole drilled into the gate post. We also for double safety had the welder weld a chain with a snap just long enough to go from just beneath the bolt to an eye bolt screwed into the wooden post next to where the bolt inserts. Even if the horses happen to slide the bolt, the gate can not swing more than 3" ...no one can get anything in between the gate & the post this way. It's so easy to open, I can do it one handed .
Kaaren